In the world I'm creating, a branch of humans from prehistoric earth were castaway to another dimension by reality bending beings. The dimension exists as a large cavern filled with giant Earth arthropods and plants. Its strange laws of physics allow both organisms to survive with no negative side effects.

But the problem with the humans is that some of these creatures have an interest in killing them with their own natural weaponry. The humans proposed a way of surrounding their own bodies in a suit of armor for further survival. But the issue I'm running into is what material could they use as armor that is effectively durable, lightweight and protective against getting punctuated by stingers, claws and mandibles?

A few materials I thought of were exoskeletons from other insects. Though the problem with exoskeleton is that stinging species could easily penetrate through.

Also for the details on the humans, they run, jump and carry as if they're on earth, so they can't lift many times their own bodyweight or run faster, but they can oddly stand on some of the arthropods without killing them, so they are light to the arthropods, but not to themselves.